3652-84-4

Usage

Uses

Bromoethane-1,1-d2 (CAS# 3652-84-4) is a useful isotopically labeled research compound.

InChI:InChI=1/C2H5Br/c1-2-3/h2H2,1H3/i2D2

Upstream product

• 1859-09-2 ethanol-1,1-d2 
• 22544-42-9 ethanol-d3 
• 60835-92-9 ethyl-1,1-d2 alcohol 4-methylbenzenesulfonate 

Downstream Products

• 19136-91-5 (2,2-d₂)-propionic acid 
• 56248-26-1 2,2-dideuterio-1-phenyl-propan-1-ol 
• 4019-57-2 (1,1-dideuterio-ethylsulfanyl)-benzene 
• 23511-00-4 1',1'-d2-4-Ethoxycyclohexanon 
• 64833-96-1 (3,3-2H2)-butyric acid 
• 1246674-41-8 C₁₅H₁₅⁽²⁾H₂N 
• 40422-14-8 2,2-dideuterio-propan-1-ol 

Relevant academic research and scientific papers

Loss of Alkanes from Ionized Branched Chain Ethers. Metastable Decomposition from an Electronically Excited State?

Ethers of the type R1CH(CH3)OR2 show a metastable peak for the loss of R1H in their mass spectra.Loss of C2H5D is the principal decomposition of metastable C2H5CH(CD3)O(+.)CH3, demonstrating that vinyl ether ions are formed by the metastable losses of alkanes.Thermochemical and orbital symmetry considerations support the hypothesis that the losses of alkanes occur from an electronically excited state of the ether ions.Other ether ions with the oxygen bonded to a nonterminal carbon also lose alkanes.N,N-Dimethyl-s-butylamine, di-sec-butyl sulfide, sec-butylbenzene, and tert-pentyl ether ions do not lose alkanes.

A Comparison between the Stereoselective Thermal-Induced and Ionization-Induced Elimination of Acetic Acid from 2-Butyl Acetate

Photoelectron photoion coincidence spectrometry shows that the ionized acetate ester of sec-butyl alcohol eliminates acetic acid just above the ionization potential but cleaves to form C2H3O+ at energies greater than 2 eV above this point.Experiments with the C-3 deiterium-labeled diastereomers of 2-butyl acetate show the elimination reaction to be stereoselective at all energies 0.1 eV greater than the ionization potential.These measurements were made by threshold photoelectron photoion coincidence spectrometry (TPEPICO).The TPEPICO stereoselective channel ratios were fit well by RRKM calculations in which the threshold energy dif ference for the stereoisomeric pathways was 600-800 cal/ mol.These numbers may be minimum values if a C-3 epimerization, i.e., stereochemical scrambling, mechanism intervenes in these ions.Such a process is probably responsible for the absence of stereoselection in the metastable ions formed in an electron-impact mass spectrometer.Published data on the thermal decomposition of 2-butyl acetate imply a difference in threshold energy for the stereochemical paths of 690-830 cal/mol.Existing mechanistic proposals for the loss of acetic acid from the ion (McLafferty rearrangement) and from the neutral suggest similar threshold energy differences for the stereoselective pathways.Integration of the microscopic stereoselective channel ratios over PEPICO-derived energy distribution function of those molecular ions which undergo elimination of acetic acid predicts the photoionization source temperature dependence of the stereoselectivity should be less than that experimentally observed in an electron-impact mass spectrometer.

Method of preparing beta-d2 alkyl acid compounds

The invention provides a method of preparing beta-d2 alkyl acid compounds. The method includes steps of: 1) performing a reduction reaction to a compound A with LiAlD4 to obtain a compound B; 2) performing -OD group protective reaction to the compound B to obtain an intermediate C; 3) performing a bromination reaction to the intermediate C to obtain a compound D; 4) under alkaline condition, performing a substitution reaction to the compound D and acetic acid to obtain the beta-d2 alkyl acid compounds. In the method, the alkyl acid, which is low in cost and is easy to obtain, is used as the initial raw material and is subjected to LiAlD4 reduction reaction, the -OD group protective reaction, the bromination reaction and the acetic acid substitution reaction to prepare the beta-d2 alkyl acid compounds. The method has simple process route and is free of expensive catalysts and the like during the reactions, is low in cost, and is high in total yield of the beta-d2 alkyl acid compounds. The method, when being amplified to gram-scale, has stable yield and good repeatability and is practicable and available.

Raman spectroscopy of n-pentyl methyl ether and deuterium labelledanalogues

The Raman spectra of n-pentyl methyl ether, C5H 11OCH3, and six selectively deuteriated analogues arereported and discussed. Correlations between the observed ν(sp 3CH)stretching and bending bands and the position of the deuterium atoms in thealkyl chain are developed and refined. Similar progress is possible inassociating specific skeletal vibrations with bands in the Raman spectra. Therelevance of this study to improving the assignment of bands in the Ramanspectra of larger systems of biological interest is highlighted. Copyright

Intermediacy of ion neutral complexes in the fragmentation of short-chain dialkyl sulfides

The main fragmentation processes after electron ionization of butyl methyl and butyl ethyl sulfides are rationalized by the intermediacy of the ion neutral complex [RSH · methylcyclopropane](+·) as demonstrated by extensive labeling and collision activation studies.

n-Caprylammonium Chloride: A Solid Membrane Model

n-Caprylammonium chloride (C8Cl) undergoes three thermotropic phase transitions between 304 and 311 K.Its high-temperature phases (β, γ, and α) are very disordered and resemble smectic mesophases found in biomembranes.The δ-phase (stable between 278 and 304 K) of C8Cl is studied by means of single-crystal X-ray diffraction.Chlorine and nitrogen atoms form a 3-periodic arrangement, but the carbon atoms oscillate about the long axes of the n-caprylammonium chains.These exist as several conformers which can be approximated as a single, entirely extended chain.The cell of the δ-phase allowed us to index powder X-ray photographs of the other phases of C8Cl and to deduce a structural description for them.Percentages of conformers, G forms, and GTG'/GTG sequences in the various phases are estimated from the analysis of characteristic IR and Raman bands, especially of the ω-bideuterated derivative.By a combination of our conclusions with previous NQR and NMR results, a rather complete picture of the phase transitions is deduced: they are brought about by the disordering of the aliphatic chains on one hand and of the hydrogen bonding scheme at the Cl-N interface on the other hand.The dynamics of these two subsystems behave quite differently indeed: changes in the chains occur very gradually, whereas variations in the interface happen quite abruptly.C8Cl successfully mimics the temperature dependence of the bilayer thickness, chain cross section, and order as well as the chain separation/interdigitation transition in biological membranes.

Gas-Phase Chemistry of CH3SOH, (-)CH2(+)SHOH, CH3SO(.), and (.)CH2SOH by Neutralization-Reionization Mass Spectrometry

The kinetically unstable molecules methanesulfenic acid (CH3SOH, 1) and its ylide isomer ((-)CH2(+)SHOH, 2) and the isomeric radicals CH3SO(.) and (.)CH2SOH exist as distinct species in the gas phase.CH3SOH was generated by flash-vacuum pyrolysis of methyl tert-butyl sulfoxide and by neutralization of the corresponding cation radical.The ylide (-)CH2(+)SHOH was prepared by neutralizaton of the distonic ion, (.)CH2(+)SHOH, generated from di-n-butyl sulfoxide by double hydrogen rearrangement.Upon collisional activation CH3SOH decomposes to CH3(.) and (.)SOH, while(-)CH2(+)SHOH affords mainly (.)CH2SH and (.)OH.Collisionally activated dissociation (CAD) spectra of the corresponding ions also distinguish these (C,H4,O,S)(.+) isomers.The isomeric radicals CH3SO(.) and (.)CH2SOH and ions CH3SO(+) and CH2SOH(+) were characterized through their neutralization-reionization and CAD mass spectra, respectively.Decomposition mechanisms consistent with deuterium labeling are proposed, and the relative stabilities of the (C,H4,O,S) isomers are estimated by MNDO calculations.

Ion-Neutral Complexes as Intermediates in the Decompositions of C5H10O2.+ Isomers

Ionized pentanoic acid, 3-methylbutanoic acid, and the enol isomer of ionized isopropyl acetate are shown to pass in part through common intermediates before decomposing to CH3C.HC(OH)2+ (7) and the "McLafferty + 1" ion CH3C(OH)2+ (10).The H transfer to form the methyl of CH3C(OH)2+ and the joining of two CH2 groups to form the C-C bond in the ethylene eliminated to produce CH3C.HC(OH)2+ are both attributed to reactions of the ion-neutral complex .H2C(OH)2+>.The McLafferty + 1 ion is also formed, especially from ionized esters, by another pathway in which complexes may or may not be intermediates.The intermediacy of the ion-neutral complexes is supported by energetic considerations, isotope effects, and the decomposition patterns of labeled ions.The latter correlate with a preference for hydrogen transfer from the end carbons of the C3 partner in other reactions proposed to be complex-mediated.Unification of the McLafferty rearrangement, the McLafferty + 1 rearrangement, and the McLafferty rearrangement with charge reversal by a common initial γ-hydrogen rearrangement followed by dissociation or isomerization in ion-neutral complexes is proposed.Group migration by 1,2-shifts, possibly by dissociation to form a double bond in one partner in an ion-neutral complex followed by addition at the opposite end of the double bond, is shown to be a general reaction of ions in the gas phase.

THE rs STRUCTURES OF PROPYL FLUORIDE AND DIFFERENCES IN STRUCTURES BETWEEN ROTATIONAL ISOMERS

Microwave spectra of trans and gauche propyl fluoride and its isotopically substituted species have been measured.The rs structures of the trans and gauche isomers of this molecule are determined from the observed moments of inertia.It is found that the CCC angle values are largely different between two isomers, while the CCF angle values stay unchanged.The rs structures of ethyl fluorosilane and ethylmethyl sulfide are re-examined in order to compare the results with those of propyl fluoride.The differences in the structural parameter values between the rotational isomers are discussed for the present molecules and the analogous molecules such as ethanethiol and ethaneselenol.

ESR, Structure, and reactions of Specifically Deuterium-Labeled Pentane Cations in X-Irradiated Freon Matrices

Solutions of 1-2 mol percent of pentane, pentane-3-d2, pentane-2,4-d4, and pentane-1,5-d6 in CFCl3, CF3CCl3, and CF2ClClFCl2 have been X irradiated at 77 K.ESR spectra of the molecular ions were recorded at temperatures between 77 K and either the glass transition temperature for CF3CCl3 (140 K) and CF2ClClFCl2 (about 110 K) or the melting point for CFCl3 (162 K).It was found that the pentane molecular ions in these matrices have not only the structure of an extended chain, but also that of several gauche conformers.Their identity and proportions depend on the matrix and on the labeling.INDO calculations were made to elucidate the detailed structure of the conformers of the pentane molecular ions in these matrices.Tilting both methyl groups toward the central-CH2- leads to a significant decrease in the energy of the ion with a minimum at about 90 deg and to significant changes in hyperfine coupling constants, giving a much better agreement with experimental data.Isotope effects were discovered for the deprotonation reaction in CF2ClCFCl2 and especially for the photofragmentation in CF3CCl3.